Originally Posted by SVMorningStar
I plan to be hauling my boat in Oct. for a bottom job. After an issue with a leaky stuffing box (coinciding with the bilge
pumps going south- fun, fun!), I am considering pulling the shaft and changing over to a dripless seal while I have it out of the water. I was wondering what downsides there might be to this kind of system. Any input or comparisons?
I've used dripless seals for over 20 years without any problems except .... and this is a rare exception. When I installed a Seahawk Autostream feathering prop the hub of the prop came within a half inch of the water (cutlass) bearing. After a long layup
in a marina we got underway and had to use the engine to get to an anchorage in front of a storm and darkness. I had a loud screeching noise
develop and on investigation found the water in the PSS was boiling! No lubricating water was getting through the water bearing, the cause of which I discovered the next day after sailing into a less than desirable anchorage, anchoring
and riding out 2 meter seas through the night. The cause was marine
growth between the prop hub and inside the water bearing which was blocking the ingress of the lubricating water. That PSS has now been replaced with one for a power boat
which has a nipple into which I run water from the drain petcock on the heat exchanger
. This positive flow lubricates the bearing nicely and the problem has gone away.
I even have an old one installed on the top of the rudder
shaft at its entry to the boat ... replacing a stuffing box there that froze to the rudder
shaft, broke the hose and nearly filled the boat when sailing downwind in large following seas.